nucleic acids Flashcards
why are nucleic acids important
they are information carrying molecules
what nuclei acids polymers of
nucleotides
whats the structure of a nucleotide
-phosphate group
-pentose
-nitrogen containing base
what are the components of an RNA nucleotide
-phosphate group
-ribose
-one of the organic bases (including uracil)
what do nucleotides join together to form
phosphodiester bonds by condensation reactions
where is the phosphodiester bond formed
between the phosphate group which is attached to the 5’ carbon on the pentose of the 1st nucleotide and the 3’ carbon on the pentose of the 2nd nucleotide
functions of nucleic acids
-DNA holds and stores genetic info and RNA transports the genetic info from DNA to ribosomes
-ribosomes themselves are made from RNA and protein
structure of nucleic acids
-DNA molecule consist of 2 polynucleotide chains held together by hydrogen bonds between specific complimentary base pairs
thymine to adenine (2 bonds)
cytosine to guanine (3 bonds)
-2 stands are twisted into a double helix
RNA molecule is formed of a single polynucleotide chain which is usually short in comparison to a DNA molecule
what does ATP stand for
adenine triphosphate
what is ATP formed with
from a molecule of ribose, molecule of adenine and 3 phosphate groups
what does ATP hydrolase do
hydrolyses the ATP and removes the last phosphate group to produce inorganic phosphate and ADP
adenine diphosphate
what type of reaction is ATP
exothermic reaction
releases the right amount of energy to be used in a single step of a biochemical process
what happens to the phosphate that is released in the hydrolysis of ATP
may be added to another compound (eg when glucose is phosphorylated it makes it more reactive so it can take part in endo thermic reaction)
steps of phosphate being added to glucose
- glucose + ATP = glucose-1-phosphate
- glucose-1-phosphate + glucose = pi + water + maltose
structure and function of DNA
-complimentary base pairs- code for genetic info
-helical structure (double)- preserves info - strong sugar phosphate backbone protects base pairs
-base pairs are joined by hydrogen bonds- weak, easily broken for replication, however many hydrogen bonds between base pairs join strands together securely giving stability
double stranded- therefore both strands can be copied in semi-conservation replication
-very long- can hold a lot of info
